Interactions electrophoresis

NHH Heegard, RT Kennedy. Identification, quantitation and characterization of biomolecules by capillary electrophoretic analysis of binding interactions. Electrophoresis 20 3122-3133, 1999. 

Riesner D, Steger G, Zimmat R, Owens RA, Wagenhofer M, Hillen W, et al. Temperature-gradient gel electrophoresis of nucleic acids analysis of conformational transitions, sequence variations, and protein-nucleic, acid interactions. Electrophoresis 1989 10 377-89. 

In particular, in polar solvents, the surface of a colloidal particle tends to be charged. As will be discussed in section C2.6.4.2, this has a large influence on particle interactions. A few key concepts are introduced here. For more details, see [32] (eh 13), [33] (eh 7), [36] (eh 4) and [34] (eh 12). The presence of these surface charges gives rise to a number of electrokinetic phenomena, in particular electrophoresis. 

Size Isomers. In solution, hGH is a mixture of monomer, dimer, and higher molecular weight oligomers. Furthermore, there are aggregated forms of hGH found in both the pituitary and in the circulation (16,17). The dimeric forms of hGH have been the most carefully studied and there appear to be at least three distinct types of dimer a disulfide dimer connected through interchain disulfide bonds (8) a covalent or irreversible dimer that is detected on sodium dodecylsulfate- (SDS-)polyacrylamide gels (see Electroseparations, Electrophoresis) and is not a disulfide dimer (19,20) and a noncovalent dimer which is easily dissociated into monomeric hGH by treatment with agents that dismpt hydrophobic interactions in proteins (21). In addition, hGH forms a dimeric complex with ( 2). Scatchard analysis has revealed that two ions associate per hGH dimer in a cooperative... 

As in CE, changing system variables (e.g., pH, ionic strength, additive concentration) is very easy in any of the continuous free flow electrophoresis systems reported here because all the interactions take place in free solution. Indeed, changing system variables may be easier in continuous free flow electrophoresis systems than in a CE system because there are essentially no wall effects. Of course, changing system variables in the continuous free flow electrophoresis apparatus may also be easier... 

Very recently, the Shipman group have made a further step towards a comprehensive structure/activity profile for noncovalent interactions between azinomycin B and DNA [152]. They synthesized simplified azinomycin analogues 69 and 96-98 (Scheme 11.13), retaining both the epoxide and aziridine alkylating functionalities, with systematically altered substitution on the naphthoate fragment, and analyzed their DNA crosslinking by gel electrophoresis. They found that cross-... 

The form of the effective mobility tensor remains unchanged as in Eq. (125), which imphes that the fluid flow does not affect the mobility terms. This is reasonable for an uncharged medium, where there is no interaction between the electric field and the convective flow field. However, the hydrodynamic term, Eq. (128), is affected by the electric field, since electroconvective flux at the boundary between the two phases causes solute to transport from one phase to the other, which can change the mean effective velocity through the system. One can also note that even if no electric field is applied, the mean velocity is affected by the diffusive transport into the stationary phase. Paine et al. [285] developed expressions to show that reversible adsorption and heterogeneous reaction affected the effective dispersion terms for flow in a capillary tube the present problem shows how partitioning, driven both by electrophoresis and diffusion, into the second phase will affect the overall dispersion and mean velocity terms. 

Chrambach, A Rodbard, D, Polyacrylamide Gel Electrophoresis, Science 172, 440, 1971. Chu, B Yeh, F Sokolov, EL Starodoubtsev, SG Khokhlov, AR, Interaction of Slightly Cross-linked Gels of Poly(diallyldimethylammonium chloride) with Surfactants, Macromolecules 28, 8447, 1995. 

These assumptions were confirmed by the electrophoresis study of the washed creams. Electrophoresis of purified fat globules is a convenient method to characterize and quantify proteins adsorbed at the oil-water interface [35]. Electrophoretic data indicate that no casein, nor whey proteins, were adsorbed at the surface of raw-milk fat globule. Upon homogenization, caseins adsorbed preferentially at the lipid-water interface. In this case, bound a-lactalbumin accounted for 16% of the total interfacial proteins. Heat treatment also induced the interaction of proteins with the fat globules. The amount of bound proteins (per mg of lipids) for heated raw milk was half that for homogenized milk. 

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